1. Field of the Invention
The present invention relates to a field of wireless communication and, more specifically, to an apparatus for and method of reselection from macrocell to femtocell.
2. Discussion of Related Art
Mobile wireless systems allow users to communicate using wireless transceivers. The mobile wireless systems include cellular telephone systems and Personal Communication Services (PCS) telephone systems. The wireless transceivers include cellular telephones, PCS telephones, personal digital assistants (PDAs), and Mobile Internet Devices (MIDs).
The mobile wireless systems are licensed by the government to access and use certain signal frequencies. Base stations are installed about a mile apart to support communication on the licensed frequencies. The base stations include cellular towers in a cellular network. Limitations in voice and data-transfer quality, rates, and range, however may result in a quality of service (QoS) of the licensed wireless systems to become lower than for conventional wired (landline) systems that constrain mobility of the users.
A femtocell is a low-power wireless access point that operates in licensed spectrum to connect standard mobile devices to a mobile operator's network using a broadband connection, such as a Digital Subscriber Line (DSL) or a cable modem. The femtocell allows a service provider to extend its service coverage indoors, especially where access would otherwise be limited or unavailable.
Handover from a macrocell to a femtocell currently requires the macrocell base station to periodically broadcast system information of all neighboring base stations in order to notify all mobile systems within range. A neighbor list of cells includes potential handover candidates for selection and redirection before the handover.
Such a protocol is, however not scaleable when a large number of femtocells is co-located with the macrocell. In particular, the current protocol may consume excessive battery power and incur unnecessary service interruptions.
Thus, a new solution is required to provide for an efficient handover when the use of femtocells is widespread.